1. Field of the Invention
The present invention relates to a network system and an image projection apparatus.
2. Description of the Related Art
As a projector can project an enlarged image, the projector has been widely used at various situations such as a meeting in an office, various kinds of presentations, a school or the like where a presenter presents an image to plural people.
Further, the projector has been developed to have plural functions in addition to a display function. Especially, the projector has been developed to have functions actualized with other devices which are connected with each other via a network. For example, a projector having a function to connect to a network, can receive an operation or an image file from a Personal Computer (PC) which is connected via the network, and decode the image file to be projected. For such an operation of the projector, generally, utility software is used. For example, the utility software is installed in the PC so that the PC can be easily wirelessly connected to the projector and file transfer an image file of a predetermined format. Thus, even when the functions are increased, the projector can be easily used.
For example, when the projector can handle a JPEG image file, a PC connected to the projector via a network converts an image file stored in the PC to be in JPEG format using utility software and sends the image file to the projector. Further, the PC converts format, resolution, color tone, and compression ratio of the image file to be capable of being handled by the projector using the utility software.
The reason for performing such processing by a PC; not by a projector is that generally, memory capacity or performance of a CPU of a projector is lower than that of the PC, or resolution of an image file capable of being handled by the projector is lower than that of the PC. Thus, it is necessary for a PC to generate an image file, which can be handled by a projector, from an image file stored in the PC, using utility software to send the generated image file to the projector.
A technique in which the projector sends an image file being projected to PCs of participants is known (see Patent Document 1 for example). Patent Document 1 discloses a technique in which an image being projected by a projector is captured to be sent to a PC of a participant as an image file. Thus, it is described that the PC of the participant can display the image file with a browser.
However, there may be a problem that the image file sent to the PCs of the participants by the projector is different from the original image file stored in the PC of the presenter.